1. Field of the Invention
The invention generally relates to an illumination apparatus, and more particularly, to an illumination apparatus having a heat dissipation structure.
2. Description of Related Art
Most of the illumination apparatuses using on the street are high voltage sodium lamps and mercury lamps. However, the high voltage sodium lamp and the mercury lamp have disadvantages of high power cost and low endurance. With the development of the technology, the light emitting diode (LED) having advantages of high illumination, high endurance, and low power cost is used as the illumination apparatus of the light source to substitute the high voltage sodium lamp and the mercury lamp having disadvantage of high power cost and low endurance. However, the enduring temperature of the LED is 120□, and once the temperature of the LED is more than 120□, the life of the LED may be reduced quickly and the LED may be damaged. Therefore, solving the heat dissipation problem of the illumination apparatus using the LED is important.
In addition, the above-mentioned illumination apparatus is used in outdoor environment, so a dustproof problem is important. Please refer to FIG. 1, an illumination apparatus 100 includes a housing 110, a light source module (not described), and a plurality of heat dissipation fins 130.
The housing 110 has a heat dissipation substrate 115 and a plurality of outlets 116. The outlets 116 are disposed at one side of the housing 110. Referring to FIG. 2 at the same time, the light source module 120 is disposed on the bottom surface of the heat dissipation substrate 115. A plurality of the heat dissipation fins 130 are disposed in the housing 110 and located on the top surface of the heat dissipation substrate 115. The heat generated by the light source module 120 on the bottom surface of the heat dissipation substrate 115 is dissipated to the heat dissipation fins 130 on the top surface of the heat dissipation substrate 115 through the heat dissipation substrate 115, and the heat dissipation fins 130 make the heat be carried from the outlets 116 of the housing 110 to the outside of the hosing 110 of the illumination apparatus 100 through the gas convection.
However, if the openings of the outlets 116 provided by the housing 110 of the conventional illumination apparatus 100 are larger, the dustproof effect of the illumination apparatus 100 may be reduced, and the dust and other foreign material may enter the housing 110 through the outlets 116 and block up the gap between the heat dissipation fins 130 and result in bad heat dissipation effect of the illumination apparatus 100 and the damage of the light source module 120. If the openings of the outlets 116 are smaller, the heat stored in the housing 100 may dissipate ineffectively, and result in bad heat dissipation effect of the illumination apparatus 100 and the damage of the light source module 120. Therefore, how to make the openings of the outlets 116 of the illumination apparatus 100 big enough to dissipate heat and have dustproof effect are problems of the technological area to solve.